Subverting every “Boy & His Pet” trope to bleak extremes, Lean On Pete plays like a “Scared Straight!” cautionary tale for following your heart.

Made with austere yet superlative craft, centered around a young lead performance of raw revelatory power, and told with an astonishing level of integrity, there’s a lot to admire in Lean On Pete as it takes you through a grueling, uncompromising odyssey.

Even so, it starts to feel honest-to-a-fault as it pummels every Disney-fied cliché with a sucker punch of reality. By the final nihilistic stretch you’re left wondering what’s the point.

Not that a thoughtful character study needs one, mind you. To explore the human condition is enough. Yet when a good kid like this has misfortune stacked against him, the story needs more than the faint glimmer of hope that the brief coda here morsels out.

Anyone walking into Lean On Pete (hopefully not with their kids, God forbid) expecting a sentimental family film is in for a rude awakening, but at least it happens immediately. Abandoned by his mom as a boy, the now 15-year-old Charley lives with his kind yet deadbeat dad Ray (Travis Fimmel, TV’s Vikings) in a shack of a house.

It’s common for Charley to wake up to breakfast cooked by his dad’s latest sexual conquest, and Ray’s table conversation is complete with casual profanity and a fresh can of beer. He’s a horrible excuse for an adult, and can even be a childish prick at times, but Charley knows that his dad didn’t feel “stuck” with him when his mom left; Ray loves his son, and Charley loves his dad.

Nevertheless, Charley’s favorite past time is running (which has a Freudian ring to it). A chance meeting with a horse trainer (Steve Buscemi) and his jockey (Chloe Sevigny) on a shady minor league circuit sets Charley running farther away than ever before, but down an unsuspecting path that never gives and only takes.

The reason he’s blind to it, just as we are, is that it starts with a connection to a race horse, named Lean On Pete. But when the gimpy stallion may be retired and sold (with a potentially ominous fate), Charley makes a foolhardy attempt to save him.

Many a feel-good family flick has been built around a similar premise, but this one chews that up and spits it out.

Lean On Pete adheres to an arc that’s infinitely more truthful than one softened by maudlin affirmations. It exists in an all-too-real world that cuts no slack for a minor’s wide-eyed idealism, especially when he has no resources to back up those heartfelt convictions. Life doesn’t reward underage vigilante rescue efforts; it’s callous towards them. And it is here.

All this sounds a bit sadist, but as Charley treks across several Western states, writer/director Andrew Haigh (45 Years) filters the adolescent’s trials and tribulations through a compassionate lens, not a cruel fetish, and Charlie Plummer (the John Paul Getty III of All The Money In The World) imbues Charley’s impulsive swings with a heartbreaking logic of quiet desperation.

But, perhaps because of this sympathetic touch, the net effect is a grind on the emotions and psyche, turning Lean On Pete into the most unexpected of one-timers. The final thirty minutes of this two-hour endurance test are particularly brutal.

What we experience by extension is a portrait of poverty in modern white, rural America, and Haigh – a Brit – depicts it with keen empathy. Indeed, his temperate verisimilitude is in stark, superior contrast to recently lauded exposés of the rural U.S. by U.K. directors.

Films like Martin McDonagh’s caricatured Three Billboards Outside Ebbing, Missouri or Andrea Arnold’s poverty porn American Honey played off foreign stereotypes and biases, not a credible understanding of the American lower class. Haigh, however, is not peddling any political agenda or cultural critique. He simply cares.

If the movie pulls any punches, it does so in bypassing consequences (some of serious legal jeopardy) for actions that Charley feels forced to take along the way. The film is punishing enough as it is, so it’s easy to be grateful for this mercy, but that grace is more a convenient plot hole than a reasoned outcome, substantiated result, or thematic ideal of humanity.

Andrew Haigh is not trying to be provocative or iconoclastic here, or if he is it’s with the most sincere intentions. Even so, Lean On Pete doesn’t so much touch your heart as it does rip it out and twist it in a vice.